1. Field of the Invention
The present invention relates to image processing apparatuses and methods, and programs, and more particularly, to an image processing apparatus and method, and a program in which the positions at which the repeating cycle of repeating components in an image appears can be specified.
2. Description of the Related Art
A technique for forming a map by extracting a building from an image photographed by a digital still camera and outputting the extracted building as an image is known.
One technique for forming a three-dimensional map is as follows, as disclosed in, for example, U.S. Pat. No. 3,267,590. A user performs a two-dimensional input operation to form a surveying map, calculates the heights of buildings, and photographs target buildings. Based on the surveying result, the user creates a general-purpose database representing two-dimensional map data provided with the heights of the buildings, and options are further added to the map data, thereby generating an integrated three-dimensional city database.
To form a map, if two-dimensional Fourier transform is performed on an image, the repeating cycle of repeating components in the image can be determined to a certain degree by detecting the peak value.
Japanese Unexamined Patent Application Publication No. 9-167240 discloses a technique for extracting edges of an image based on a combination of the difference of pixels of digitized image data.
To form a map, if an image is divided into a plurality of blocks, generally, the numbers by which the image is divided in the horizontal direction and in the vertical direction are set based on the size of the image, and the block size is determined based on the numbers of divided portions.
For example, U.S. Pat. No. 3,364,939 discloses a technique for spatially dividing image data into a plurality of blocks, one block having n×n pixels.